AATIAN77 Datasheet, PDF (2/4 Pages) SiGe Semiconductor, Inc. – I/O Expander Switch with Serial Control

EV-112
AAT4290IJS-1-DB3 EVAL
I/O Expander Switch with Serial Control
Getting Started
The AAT4290IJS-1-DB3 evaluation board is typically mounted on a battery pack. The battery pack holds three
AAA size, conventional alkaline batteries. A jumper is inline with the battery supply for connecting/discon-
necting power. There is an additional jumper labeled ON SRL OFF, which provides access to EN/SET. Ensure
that the jumper is in the ON SRL position for normal operation. To apply power to the board, ensure the jumper
is at the ON MCU position. The red LED1 should illuminate indicating that power has been connected.
The AAT4290 may be operated from an external power source. The batteries should be removed from the bat-
tery pack. External power may be applied to the DC+ and DC- points on the board. The external power source
should be set from 1.8V to 5.5V before the AAT4290 is turned on by moving the jumper on J1 to the “ON MCU”
position.
There are three buttons on the board (SW1, SW2, and SW3) that enable and disable the ON and OFF state
for the five output channels. Once a button (or a combination of buttons) is toggled, the corresponding LED
for OUT1 to OUT5 will turn ON or OFF accordingly, depending on the previous state. This indicates that the
selected state has been submitted through the EN/SET line to the AAT4290. Detailed operations are listed in
Table 1. Toggling SW1 and SW3 at once, activates the auto-cycling state through the "AAT4290 Output
Settings" table found in the product datasheet. In other words, the microcontroller will submit a burst of edges,
pause, and submit another burst of edges and so on. It will start by submitting 31 edges, next submit 30 edges,
etc.; next, submit 1 edge and then start over. All LEDs should blink five times before the sequence of auto-
cycling. By toggling all three buttons together, all LEDs should turn off.
The AAT4290 outputs can be probed via the test points near the output capacitors (C4 to C8).
Button(s) Pushed
SW1
SW2
SW3
SW1 + SW2
SW2 + SW3
SW1 + SW3
SW1 + SW2 + SW3
Description
Toggle on/off of output Channel 1.
Toggle on/off of output Channel 2.
Toggle on/off of output Channel 3.
Toggle on/off of output Channel 4.
Toggle on/off of output Channel 5.
Auto cycling. All outputs blinks (on and off) five times and enter binary-
increment mode. Auto cycling repeats three times.
Reset. All outputs turn off.
Table 1: User Interface Functionality.
2
EV-112.2005.06.1.0